CVE-2026-117862

Published Oct 27, 2026 Modified Oct 27, 2026

Description

Privilege escalation due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.

Is your site exposed to CVE-2026-117862?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0053

Probability of exploitation

0.45%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=2054644 https://www.mozilla.org/security/advisories/mfsa2026-118/ https://www.mozilla.org/security/advisories/mfsa2026-119/ https://www.mozilla.org/security/advisories/mfsa2026-120/ https://www.mozilla.org/security/advisories/mfsa2026-121/ https://www.mozilla.org/security/advisories/mfsa2026-122/

Frequently Asked Questions

What is CVE-2026-117862? +

How do I check if I'm vulnerable to CVE-2026-117862? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.